Early diagnosis and follow-up of acute schistosomiasis in a cluster of infected Belgian travellers by detection of antibodies and circulating anodic antigen (CAA) a diagnostic evaluation study

Hoekstra, P.T.; Esbroeck, M. van; Dood, C.J. de; Corstjens, P.L.A.M.; Cnops, L.; Zeijl-van der Ham, C.J.G. van; ... ; Lieshout, L. van (2021)

Article / Letter to editor

Background: In order to evaluate the diagnostic value of schistosome circulating anodic antigen (CAA) detection, serum and urine CAA-levels were determined in a single cluster of 34 Belgian tourists at three timepoints within a period of 14 weeks following proven Schistosoma exposure in South Africa and compared with two in-house antibody assays. Methods: Samples were collected 4-5 and 7-8 weeks post-exposure and subsequently 5-6 weeks following praziquantel treatment. Schistosoma antibodies were detected by an adult worm antigen-immunofluorescence assay (AWA-IFA) and a soluble egg antigen-enzyme-linked immunosorbent assay (SEA-ELISA), while CAA concentrations were determined by the Up-Converting reporter Particle labelled Lateral Flow (UCP-LF) test. Results: Antibodies were detected in 25/34 (73%) travellers pre-treatment and in 27/34 (79%) post-treatment, with the AWA-IFA showing better performance than the SEA-ELISA. Pre-treatment, CAA was detected in 13/ 34 (38%) and 33/34 (97%) of the travellers in urine and serum, respectively. Post-treatment, all except one traveller became serum CAA negative. This in contrast to the detected antibodies, as well as the previously reported diagnostic results of this cluster. Conclusions: The UCP-LF CAA serum assay has been demonstrated as the most sensitive method for the diagnosis of early Schistosoma infections and post-treatment monitoring in travellers.

• Schistosoma haematobium complex
• Circulating anodic antigen
• Diagnostic accuracy
• Sensitivity
• Treatment efficacy

• All authors: Hoekstra, P.T.; Esbroeck, M. van; Dood, C.J. de; Corstjens, P.L.A.M.; Cnops, L.; Zeijl-van der Ham, C.J.G. van; Wammes, L.J.; Dam, G.J. van; Clerinx, J.; Lieshout, L. van
• Date: 2021-05-01
• Journal: Travel Medicine and Infectious Disease
• Volume: 41
• DOI: doi:10.1016/j.tmaid.2021.102053
• Link: https://www.sciencedirect.com/science/article/pii/S1477893921000946?via%...